export {}; //

let name: string = "abcdef";
let age: number = 100;
let success: boolean = true;

// name = 100

let mynamne: String = "abcdef";
console.log(name.length);
console.log(mynamne.length);

let myname2 = new String("abddsfsaf");

let smallStr: string = "abcstr";
let bigStr: String = "abcstr";

//尽量少用any
let obj: any = "jshand";
obj = 100;
obj = {};

let unObj: unknown;

unObj = "abcdef";

let num1: number = 100;
//报错
// num1 = unObj;
